Coated straw for modifying sour taste

ABSTRACT

A coated straw useful for improving the taste of acidic liquids including carbonated beverages or fruit juices. The inside surface of the straw end inserted in the liquid is coated with a mixture of nontoxic alkaline material and sugar and a separate section of the inside surface is coated with taste-modifying stable miraculin. The amount of alkaline material is sufficient to render nonacid the liquid in the first mouthful.

United States Patent Inventor Robert J. Harvey Sudbury, Mas.

Appl. No. 28,963

Filed Apr. 15, 1970 Patented Nov. 16, 1971 Assignee Medltron, Inc.

Wayland, Mass.

COATED STRAW FOR MODIFYING SOUR TASTE 8 Chime, No Drawings PrimaryExaminerTim R. Miles Attorney-Kenway, Jenney & Hildreth ABSTRACT: Acoated straw useful for improving the taste of acidic liquids includingcarbonated beverages or fruit juices. The inside surface of the strawend inserted in the liquid is coated with a mixture of nontoxic alkalinematerial and sugar and a separate section of the inside surface iscoated with taste-modifying stable miraculin. The amount of alkalinematerial is sufficient to render nonacid the liquid in the firstmouthful.

1 coxr'rzn smw son MODIFYING sour: TASTE COATED STRAW FOR MODIFYING SOURTASTE This invention relates to a straw coated with an alkaline materialand miraculin useful for modifying the taste receptors to rendersour-tasting liquids sweet tasting.

Synsepalum dulcificum Daniell, Sapotaceae is a plane indigenous toWest-Central Africa which bears a red ellipsoid fruit commonly known asmiracle fruit." The fruit has a palatable pulp and skin and contains alarge seed. It is characterized by a pleasant taste and by the uniqueproperty, well recognized for over 200 years, of modifying the sweet andsour tastes in an unusual manner. It has been found that a component inthe fruit depresses the sour taste and accentuates the sweet of anynormally sour food eaten within a short period after first contactingthe tongue with the pulp of fresh miracle fruit, thus causing thenormally sour food to taste pleasantly sweet. By exposing the tastereceptors on the tongue to miracle fruit, any sour-tasting food can bemade to taste sweet without the addition of sugar or artificialsweeteners. For example, fresh lemon can be made to taste pleasantlysweet by first eating a miracle fruit berry. The taste-modifyingprinciple in the miracle fruit berry known as miraculin binds itself tothe taste receptors thus altering the sensory perception of the sourtaste in foods eaten after the miracle fruit.

It has been determined that miraculin is a glycoprotein having amolecular weight of about 44,000. A wide variety of approaches have beenexplored in attempts to isolate the active component in miracle fruitfor subsequent use as a taste-modifying material. These attempts havemet with only limited success since the form of the product obtained bythese methods is less effective than the natural fruit, and was found tobe highly unstable at normal room temperatures under normal atmosphericconditions. This instability necessitated either very quick use afterisolation or storage at very low temperatures or under desiccatedconditions. This instability is not confined to the concentratesobtained by present processes but is also a characteristic of the fruititself. The fruit must be consumed within a very short period afterpicking or it will be ineffective in modifying sour taste.

The prior art has regarded miraculin as a very labile materialaccounting for the observed instability of concentrates maintained atnormal room temperatures. While some degree of success has been attainedin improving stability of miraculin-containing material in the order ofabout a week or so, it has been found that stability could not beachieved when maintained in powder form at room temperatures.Alternatively, the miraculin-containing material was dissolved inspecific solvents maintained at specific pH. These solutions had to berefrigerated to be preserved, and even then this material was not asefi'ective as the natural fruit.

The miraculin is present in the pulp and on the inner surface of theskin of the miracle fruit and in its natural environment is quicklydeactivated especially when exposed to the air once the skin is brokenat room temperatures. Furthermore, after the fruit has been picked, evenprior to breaking the skin, the active material begins to degrade but ata slower rate than when the skin is broken. While the process by whichdegradation proceeds is not known exactly, it is now believed thatcertain enzymes and/or acids present in the fruit accelerate degradationin the presence of air at normal room temperatures, and apparently evenat temperatures below the freezing point of water. it has been foundthat when the pulp of miracle fruit is frozen and subsequentlylyophilized to form a granular or powder material, the product had to berefrozen in order to maintain the activity of the material thatremained. Even when the pulp had been lyophilized, its effectiveness wasnot nearly as great, either on a weight basis or on a quality basis, asthe active principle in the fresh fruit.

A novel powdered form of the glycoprotein active principle from miraclefruit which is stable for long periods of time of a year or more atnormal room condition and is method of preparation is disclosed incopending application filed concurrently herewith in the names of RobertJ. Harvey and J. Richard Fennel].

The product disclosed in the copending application is a stable whitepowder comprising miraculin, either alone or admixed with material inertwith respect to the characteristic of suppressing sour taste butexcluding components that degrade miraculin present in the pulp and skinor miracle fruit including the material containing acids and/or enzymesthat degrade miraculin. The product exhibits remarkable stability inpowdered form at room temperature. This is indeed surprising in view ofthe prior art which regarded miraculin to be highly unstable andthen'nolabile such that it was thought necessary to maintain powderedconcentrates in a frozen condition or in a dry atmosphere or torefrigerate solutions of the active principle obtained by the prior artprocesses to retain the desired stability over reasonably long periodsof time.

The stable powdered miraculin becomes denatured when admixed with acidsolutions or altered so as not to readily bond to the taste receptors.Therefore, when it is desired to improve the taste of acid solutions,such as carbonated beverages or fruit juices, with the miraculin, it isnecessary that the miraculin be administered first and separate from thesolution. It would be advantageous to provide a means whereby themiraculin can be administered contemporaneously with the acidic liquidto provide improved convenience without substantial miraculindegradation.

In accordance with this invention there is provided a straw coated onthe inside with stable taste-modifying miraculin and a nontoxic alkalinematerial. The alkaline material is coated at the end of the strawinserted in the liquid to be drunk. During use, the acidic liquid firstentering the straw is neutralized by the alkaline material therein. Theneutralized liquid then contacts the miraculin and becomes a carrier forthe miraculin to bring it into the mouth. While in the mouth, themiraculin modifies the taste receptors as described above so thatsubsequent acidic liquid is made to taste pleasantly sweet.

The straw can be coated in any configuration so long as the firstmouthful of liquid is neutralized by the alkaline material prior tocontacting the miraculin. One configuration comprises a straw coated atone end along the inside surface and coated with miraculin on the insidesurface at a separate portion of the straw. Another configurationcomprises coating both ends of the straw along the inside surface withalkaline material while the central portion of the inside surface iscoated with miraculin. The latter configuration has the advantage ofeliminating the consequence of mistakenly placing the wrong end of thestraw in the acidic liquid and therefore is preferred. A thirdconfiguration comprises coating the straw with miraculin along all or aportion of its length and coating the miraculin layer with alkalinematerial along the entire length of the straw.

The amount of alkaline material employed is that which will neutralizesubstantially all the acid in solution during the first pass of liquidthrough the straw for the first mouthful. Thus, the length of the strawcoated with alkaline material depends upon the particular alkalinematerial employed and the diameter of the straw. It is preferred thatthe straw diameter be less than about one-quarter inch to reasonablyinsure substantial neutralization prior to contact of solution with themiraculin. Generally, the desired effect of neutralization followed bymiraculin pickup into the mouth can be efiected with a straw about 8inches or more in length.

The alkaline material can be used along or admixed with pleasant-tastingcomponents such as sugar to reduce its salty taste and to cause thefirst mouthful of beverage to taste sweet since the miraculin will nothave become effective at that point. Similarly, the miraculin can beadmixed with small amounts of sugar for the same purpose. By includingin the miraculin composition additional alkaline material the acidsnormally found in the mouth are neutralized and a greatly reduced amountof miraculin, in the order of about 50 percent is needed to obtain thedesired taste-modifying effect. After the mouth acids have beenneutralized, the miraculin is free to become bonded to the sour tastebuds.

Suitable nontoxic alkaline materials that can be employed herein includemagnesium carbonate, sodium bicarbonate, aluminum trisilicate, calciumcarbonate, aluminum hydroxide complexes such as aluminum hydroxidemagnesium carbonate codried gels, aluminum hydroxide or mixture thereof.Usually the alkaline material is employed in amounts of between 50 and250 milligrams per straw while the micraculin is employed in amounts ofbetween 0.1 and 200 milligrams per straw. When used, from about 1 to lgrams of sugar are employed per straw.

While more miraculin than set forth above can be incorporated in eachunit dosage from, it is unnecessary to do so in order to obtain thedesired taste-modifying effect. The powdered miraculin either in thepowder or in the tablet has an average particle size less than about50-60 microns. it is preferred to minimize the average particle size ofthe active material since it has been found that an even greaterreduction of the effective unit dose of active material is obtainedthereby and the miraculin becomes fully effective in a shorter time.

Any generally employed straw materials and constructions are useful inthe present invention including plastics such as polyethylene orpolypropylene and wax-coated paper.

The following example illustrates the present invention and is notintended to limit the same.

EXAMPLE I Two homogenous powdered mixtures were prepared and placed inseparate containers. One mixture comprised 10 parts confectionary sugarand one part sodium bicarbonate by weight. The other mixture comprisedone part stable miraculin obtained by the process of the above-citedcopending application and one part of the sodium bicarbonate-sugarmixture. Coated straws were prepared by inserting a 3/32-inch rod in a5/32-inch I.D., 8-inch wax-coated paper straw and tamping the straw intothe mixture. The straw first was tamped into the bicarbonate-sugarmixture until about 40 percent of the straw was filled. The straw thenwas transferred to the micaculin powder (about mesh size), the samestraw-end down, and tamped until an additional 20 percent of the strawwas filled. The straw then was transferred to the bicarbonatesugarmixture, the same end down, and tamped to fill the remaining portion ofthe straw. The rod then was removed. The straw was then used to drink aflavored carbonated beverage. the taste of which was substantiallyimproved.

I claim:

l. A straw coated on the inside with a nontoxic alkaline material andmiraculin powder in a configuration so that liquid first passed into thestraw first contacts the alkaline material to render it nonacidic andthen contacts the miraculin to carry it into the mouth.

2. The straw of claim I wherein the miraculin is coated on a centralportion of the inside surface and the remaining inside surface is coatedwith alkaline material.

3. The straw of claim 1 wherein the alkaline material is coated on oneend portion and the miraculin is coated on the other end portion.

4. The straw of claim 1 having a sweetening agent admixed with thealkaline material.

5. The straw of claim 2 having a sweetening agent admixed with thealkaline material.

6. The straw of claim 3 having a sweetening agent admixed with thealkaline material.

7. The straw of claim 1 wherein the alkaline material is sodiumbicarbonate.

8. The straw of claim 2 wherein the alkaline material is sodiumbicarbonate. I

a a a a a UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PatentNo. 3,620, 770 Dated November 16 1971 Robert J. Harvey Inventor(s) It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, line 75, after "application" insert United States Serial No.,28,981 entitled "Taste-modifying Composition and Method of Preparation."

Signed and sealed this 7th day of November 1972.

(SEAL) Attest:

EDWARD M. FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents po'wso (10459) USCOMM-DC sows-Pea U 5 GOVERNMENT PRINTINGOFFICE 19.9 0-365-3J4

2. The straw of claim 1 wherein the miraculin is coated on a centralportion of the inside surface and the remaining inside surface is coatedwith alkaline material.
 3. The straw of claim 1 wherein the alkalinematerial is coated on one end portion and the miraculin is coated on theother end portion.
 4. The straw of claim 1 having a sweetening agentadmixed with the alkaline material.
 5. The straw of claim 2 having asweetening agent admixed with the alkaline material.
 6. The straw ofclaim 3 having a sweetening agent admixed with the alkaline material. 7.The straw of claim 1 wherein the alkaline material is sodiumbicarbonate.
 8. The straw of claim 2 wherein the alkaline material issodium bicarbonate.